Objective To study the recovery mechanism of dysphagic patients after stroke using functional magnetic resonanee imaging(fMRI). Methods Thirteen patients with dysphagia caused by unilateral cortical or subcortical lesions were recruited into a dysphagia group,and eight age-matched healthy volunteers were recruited as controls.Both grouDs performed experimental volitional swallowing tasks during fMRI studies.All patients of the dys-phagia group received rehabilitation treatment targeting dysphagia.Of the 13 dysphagia patients,7 reached almost complete recovery and were identified as recovered in follow-up fMRI studies.A 3.0 T MR scanner and echo planar imaging(EPI)T_2 WI sequence were employed to obtain the fMRI data.SPM2 software was used for post-processing of the fMRI data and displaying activated brain maps.Lateral index(LI)was calculated as LI:(C-1)/(C+I).Paired t tests were used to compare activated brain volume before and after complete recovery. Results Consistent activation of the bilateral primary sensorimotor cortex,anterior cingulated gyrus and the bilateral insular cortex were observed in the control group. Activation of the pons,medulla,left cerebellum,left prefrontal area,right occipital area and the left insular cortex were observed in the dysphagia group.Activation was observed in the bilateral primary sensorimotor cortex.bilateral prefrontal area,bilateral superior temporal gyrus,left insular cortex,bilateral frontal o-pereulum and anterior cingulated gyrus in the recovered patients.The total activated volume before recovery in the ip-silesional hemisDhere was significantly less compared with the contralesional hemisphere in the dysphagia group.In the recovered patients,both the activated brain volume of the ipsilesional hemisphere and value of LI were significant-ly larger than those at the initial examination.Conclusions Decreased activation in the sensorimotor cortex,the in-sular lobe and the cingulate gyms might be causes.of dysphagia.Compensation by the contralesional hemisphere in the early stages and then the restoration of the ipsilesional hemisphere after recovery may be mechanisms of dysphagia recovery in stroke patients.

English training is important for young doctors＇ career development in general hospital.The stagewise English training mode of Beijing Tiantan Hospital of Capital Medical University was introduced.By summarizing the experience of five years trial,viewpoints were brought forward that hospital English training in radiological department of general hospital should adopt a stagewise mode,create an English communication atmosphere,show the special feature of department and combine with clinical daily work.

BACKGROUNDTo investigate the relationship among the CT appearances, the dynamic CT enhancement and the microvessel density (MVD) of peripheral lung cancer.

METHODSThirty-three patients with peripheral lung cancer proved by surgery and pathology underwent enhancement dynamic CT scan before operation, including 14 squamous cell carcinoma and 19 adenocarcinoma. The MVD was measured in resected tumor specimens with immunohistochemical method of LSAB.

RESULTSThe MVD value of adenocarcinoma was significantly higher than that of squamous cell carcinoma (63.4±11.9 versus 50.2±16.3, P < 0.05). The MVD values were higher in junction zone and interstitial areas than those in parenchymal areas, necrotic zones and scar areas of tumors. There were significant relationships among the MVD value and diameter of tumor, lobulation sign, vessel convergence sign, pleural retraction sign and lymph node metastasis (P < 0.05 ). The mean enhanced CT values was (43.4±11.8) HU in adenocarcinomas, and (34.6±10.7) HU in squamous cell carcinomas (P < 0.05). The CT values of both adenocarcinoma and squamous cell carcinoma had positive correlations to their corresponding MVD values (r=0.719, P < 0.01;r=0.819, P < 0.01).

CONCLUSIONSThe CT appearances and the enhanced CT values of peripheral lung carcinomas are closely related to their MVD values, which might be an indicator to identify the histological classification and to predict the malignant degree of tumor.

Objective To evaluate the use of diffusion-weighted imaging(DWI)for early detection of tumor response to Angiostatin-Endostatin(Statin-AE)fusion gene therapy in a rat C6 glioma model.Methods Fifty male wistar rats with C6 tumor cells implanted into the striatum were examined by a 3.0T MR scanner,then the rats beating tmors were divided into two groups,treatment group and control group.Rats in the treatment group received 107 plaque forming unit(pfu)recombinant herps simplex viral (R-HSV)mediated Statin-AE fusion gene therapy on day 7,and then the tumors were conformed on MRI.Conventional MR and DWI examination were acquired on 1,2,3 weeks after implantation with a 5-inch surface coil.Two(1 w),eight(2 w)and all the residual rats(3 w)of each group were sacrificed to perform the histopathological examination after each MBI examination.Pretreatment and post treatment tumor volulnes and apparent diffusion coefficient(ADC)values were calculated.Rank sum test and t test were employed for statistical analysis.Results On MRI,43 rats demonstrated tumors on day 7 with a successful rate of 86%,On week 2,the tumor volumes of the controh and treatment group were 90.6 and 91.64 mm3,with no significant difference(Z=-0.14,P＞0.05).On week 3,the tumor volumes of the controls and treatment group were 156.64 and 29.64 mm3,and a significant difference was observed(Z=-3.45,P＜0.01).On week 2.the ADC values of the tumor centers of the treatment group and the control group were (1.20±0.25)×10-3 and(0.99±0.08)×10-3 mm2/s,and the values of the tumor peripheral parts of the two groups were(1.00±0.25)×10-3 and(0.83±0.12)×10-3mm2/s,the ADC values of both tumor centers and peripheral parts of the treatment group were significantly higher than those of the control group (t=-0.82 and-0.46,P＜0.05).On week 3,the ADC values of the tumor centers of the treatment group and the control group were(0.92±0.21)× 10-3 and(0.99±0.09)×10-3mm2/s,and the values of the tumor peripheral parts of the two groups were(0.81±0.19)×10-3 and(0.78±0.11)×10-3 mm2/a,there were no statisfical difference between the two groups(t=0.82,and-0.46,P＜0.05).HE stained slices showed more prominent tumor interstifial edenla.swelling and death of tumor cells in the treated rats than the controls.Conclusions Combination of conventional MRI and DWI can be powerful to monitor tumor progression and therapy effecL Conventional MRI showed that the therapy slow the tumor progression in size while DWI demonstrated the tumor response even earlier than size change.DWI has potential use forthe detection of early response to antiangiogenic gene therapy.

Objective:To investigate the functional imaging parameters that effectively distinguish isocitrate dehydrogenase (IDH) gene mutation status in clinical practice with long echo time (TE) point-resolved spectroscopy (PRESS) MRS.Methods:Totally 25 patients with suspected diagnosis of low grade gliomas(LGGs; Grade II) were recruited prospectively and divided into IDH mutation group and IDH wild group according to pathological results in the study. All patients were scanned with long TE PRESS MRS. In addition, IDH mutational status was determined by post-operation Sanger sequencing. The t test or Mann-Whitney U test was used to analyze the differences of 2-hydroxyglutarate (2HG), Glutamate (Glu), Glutamine (Gln) and 2HG/Glu+Gln between the IDH mutation group and the IDH wild group, then ROC curve was plotted with statistically significant indexes to obtain the efficacy of predicting IDH mutation status. Results:Of the 25 patients, 19 had IDH mutant gliomas and 6 had IDH wild-type gliomas. 2HG, Glu, Gln and 2HG/Glu+Gln in IDH mutated group were 1.42 (1.09, 1.93)mmol/L, (1.74±1.31)mmol/L, (1.68±0.66)mmol/L, 0.55 (0.28, 0.77), respectively; while the corresponding values were 0.00 (0.00, 1.30)mmol/L, (3.28±1.02)mmol/L, (2.55±1.47)mmol/L, 0.00 (0.00, 0.26) in IDH gene wild type group, respectively. The differences of 2HG, Glu, and 2HG/Glu+Gln between the two groups were statistically significant ( P values were 0.030, 0.016, 0.004, respectively). The area under the ROC curve of 2HG/Glu+Gln was the largest (0.877), and the sensitivity was the highest (84.2%). Conclusion:The integration of 2HG with Glu and Gln can effectively realize the noninvasive assessment of IDH mutation status.